Magnetocaloric refrigeration is an emerging technology which has potential to be more efficient than conventional vapor compression systems. In the current movement toward energy efficiency, there is a desire to develop a residential refrigerator with at least 25% lower energy consumption relative to current minimum efficiency standards. Conventional refrigerators typically utilize vapor compression cycles and require high GWP refrigerants. An efficient magnetocaloric refrigerator in the market would eliminate the need for such refrigerants.
There are many challenges to design and build an effective magnetocaloric refrigeration unit. Such challenges include materials, magnets, and machine design. Challenges in the material and machine design include: a) hydraulics and sealing problems associated with complicated rotary valve systems required in such systems; and b) material degradation due to density and volume change in material over consecutive cycles. Existing magnetocaloric systems use water or other working fluids to transfer heat to the hot and cold heat exchangers. As a result, pumping systems and complicated valve systems are required. Also, a majority of the existing systems utilize a powdered magnetocaloric material for a generator which is not stable over time due to the rubbing or grinding effect caused by volume change in in the presence of the magnetic field.
A need exists for a refrigerator designed to use the magnetocaloric (MC) refrigeration effect in an efficient manner rather than conventional refrigeration models.